A Gentle Introductionto Bilateral Filteringand its Applications

A Gentle Introductionto Bilateral Filteringand its Applications

Sylvain Paris – MIT CSAIL

Pierre Kornprobst – INRIA Odyssée

Jack Tumblin – Northwestern University

Frédo Durand – MIT CSAIL

• The bilateral filter is becoming in computational photography.

• Many applications with high quality results.

Photographic Style Transfer[Bae 06]Photographic Style Transfer[Bae 06]

input

Photographic Style Transfer[Bae 06]Photographic Style Transfer[Bae 06]

output

Tone Mapping[Durand 02]Tone Mapping[Durand 02]

HDR input

Tone Mapping[Durand 02]Tone Mapping[Durand 02]

output

input

Cartoon Rendition[Winnemöller 06]Cartoon Rendition[Winnemöller 06]

Cartoon Rendition[Winnemöller 06]Cartoon Rendition[Winnemöller 06]

output

6 papers atSIGGRAPH’07

6 papers atSIGGRAPH’07

Goal: Image SmoothingGoal: Image Smoothing

Split an image into:

• large-scale features, structure

• small-scale features, texture

input smoothed(structure, large scale)

residual(texture, small scale)

Gaussian Convolution

BLUR HALOS

Naïve Approach: Gaussian BlurNaïve Approach: Gaussian Blur

Impact of Blur and HalosImpact of Blur and Halos• If the decomposition introduces blur and

halos, the final result is corrupted.

Sample manipulation:increasing texture

(residual × 3)

input smoothed(structure, large scale)

residual(texture, small scale)

edge-preserving: Bilateral Filter

Bilateral Filter: no Blur, no HalosBilateral Filter: no Blur, no Halos

input

increasing texturewith Gaussian convolution

H A L O S

increasing texturewith bilateral filter

N O H A L O S

Many Other OptionsMany Other Options

• Bilateral filtering is not the only image smoothing filter– Diffusion, wavelets, Bayesian…

• We focus on bilateral filtering– Suitable for strong smoothing used in

computational photography

– Conceptually simple

Content of the CourseContent of the Course

All you need to know about bilateral filtering:

– Definition of the bilateral filter

– Parameter influence and settings

– Applications

– Relationship to other filters

– Theoretical properties

– Efficient implementation

Course MaterialCourse Material

• Course webpage (google “bilateral filter course”):http://people.csail.mit.edu/sparis/siggraph07_course/

– Detailed course notes

– Slides (soon)

– C++ and Matlab code

– Links

A Gentle Introduction to Bilateral Filtering and its ApplicationsA Gentle Introduction to Bilateral Filtering and its Applications

• From Gaussian blur to bilateral filter – S. Paris

• Applications – F. Durand

• Link with other filtering techniques – P. Kornprobst

• Implementation – S. Paris

• Variants – J. Tumblin

• Advanced applications – J. Tumblin

• Limitations and solutions – P. Kornprobst

BREAK